The proposed study's overarching goal is to reduce the ethnic disparities in HIV infection between Hispanic and non-Hispanic youth living in Miami-Dade County, an HIV epicenter. This goal will be accomplished by two aims: AIM 1 is to develop and manualize a one-and-a-half- month streamlined version of an efficacious HIV preventive intervention entitled Familias Unidas;and AIM II is to evaluate the efficacy of the streamlined version of Familias Unidas plus an HIV Prevention School CurriculumTreatment as Usual, relative to the HIV Prevention School Curriculum Treatment as Usual only, in preventing drug use and unprotected sexual behavior, two risk factors for HIV infection. Familias Unidas aims to prevent drug use and unprotected sexual behavior by (a) increasing family functioning, (b) increasing parental monitoring of peer activities, and (c) influencing adolescent social cognitive mechanisms regarding drug use and unsafe sexual behavior. A sample of 240 Hispanic 9th grade adolescents and their primary caregivers will be randomized to one of two conditions: Familias Unidas plus the HIV School Curriculum Treatment as Usual (hereafter refererred to as Familias Unidas) or the HIV Prevention School Curriculum Treatment as Usual only. Two studies have demonstrated the efficacy of an intensive, 9 to 12 month version of Familias Unidas. In the first study, Familias Unidas was shown to be efficacious relative to a no- intervention control condition in increasing family functioning. In the second study, Familias Unidas was found to be efficacious in preventing drug use and unsafe sexual behavior relative to two attention control conditions. Hierarchical Linear Modeling (HLM) will be used to test: (H1) Familias Unidas will be more efficacious than the HIV Prevention School Curriculum Treatment as Usual in preventing adolescent drug use over time and (H2) Familias Unidas will be more efficacious than the HIV Prevention School Curriculum Treatment as Usual in preventing adolescent unprotected sexual behavior over time. Additionally HLM will be used to determine whether (H1a) the effect of Familias Unidas on drug use will be partially mediated by (1) family functioning;(2) parental monitoring of peers;and (3) social cognitive mechanisms regarding drug use;and (H2a) the effect of Familias Unidas on unprotected sexual behavior will be partially mediated by (1) family functioning;(2) parental monitoring of peers;(3) social cognitive mechanisms regarding unprotected sex;and (4) drug use. The objective of the proposed study is to reduce HIV contraction health disparities in Hispanic populations. The knowledge expected to be gained from this study will aid in the development of interventions to reduce drug use, unprotected sexual behavior, and HIV in Hispanic adolescents.